Safety-shield for circular saws



C. N. SMITH.

SAFETY SHIELD FOB CIRCULAR SAWS.

APPLICATION FILED lULY 29.1918.

1,397,606, v Patented Nov. 22, 1921.

lllll w 5.? g i 1 g l I: iii

gmuiimu [N VEN TQR.

wws mm c. N. SMITH.

SAFETY SHIELD FOR CIRCULAR SAWS.

' APPLICATION FILED JULY 29,1918. 1 397 606. Patented Nov. 22, 1921..

3 SHEETS-SHEET 2.

A TTORNLY I 1 Li C. N. SMITH.

SAFETY SHIELD FOR CIRCULAR SAWS.

APPLICATION FILED JULY 29,1918.

1,397,606, Patented Nov. 22, 1921.

3 SHEETS-SHEET 3.

ATTORNEY PATENT QFFICE.

CHRISTIAN N. SMITH, OF ELGIH, ILLINOIS.

SAFETY-SHIELD FOE- CIRCULAR SAVJS.

Application filed July 29, 1918.

To all 'w/wm 2'25 may concern.

Be it known that I, CHRISTIAN N. SMITH, a citizen of the United States, residing in Elgin, in the county of Kane and State of Illinois, have invented certain new and useful Improvements in Safety-Shields for Circular Saws, of which the following is a specification.

The principal object of the invention is to provide a simple, economical and efiicient safety shield or guard for circular saws.

A further object of the invention is to provide a circular saw' shield or guard which is adapted to be adjusted and supported in different adjusted positions successively as desired, so as to serve its purposes in an efficient manner as a shield or guard when the saw is in operation for any of the uses or purposes for which it is intended, such, for instance, as cutting or trimming electrotypes, stereotypes, halftones, zinc plates, copper plates or other metallic plates or printing plates of varying dimensions and thickness.

A further object .of the invention is to provide a circular saw shield or guard adapted to shield or guard a circular saw in such a manner as to pr vent injury to the operator or to the saw or safety device or to the work or material operated upon,- such, for instance, as electrotypcs, stereotypes, zinc, or copper plates or other metallic ness-and to enable the saw and the work or material operated upon to be visible to the operator during the operation of sawing or trimming such articles or material.

Other and further object-s of the invention will appear from an examination of the following description and claims, and from an inspection of the accompanying drawings, which are made a parthereof.

The invention consists in the features, combinations, parts, and details of construction herein described and claimed.

In the accompanying drawings, Figure 1 is a plan View of a safety shield or guard constructed in accordance with my invention, showing the same mounted in operative position in connection with a bed or table of a saw or trimming machine;

Fig. 2 is a viewin side-elevation of the device or mechanism shown in Fig. 1, showing the adjustable shield or guard in lowered operative position, in full lines, and in raised position in broken lines;

Specification of Letters Patent.

of its supporting 'tion, taken on line l upon which a circular saw 3 is supported by means of a suitable axle or known, or suitable form. 111 the drawings is provided with the usual Patented Nov. 22, 1921.

Serial No. 247,278. v

Fig. 3 is an enlarged detail view in vertical section, taken on line 3 of Fig. 1, looking in the direction of the arrow, and showing the hollow safety guard upon the extremity arm in lowered operative position in full lines, as it would appear when comparatively thin plates or articles are being sawed or trimmed, the hollow outer guard member being shown in broken lines in raised operative position suitable for use in doing work upon relatively thick or type-high material;

Fig. 4 is a view in transverse vertical secof Fig. 3, looking in the direction indicated by the arrow.

5, is an enlarged detail view in central longitudinal vertical section of another form of my improved safety shield for saws in which the stationary guard member shown in Figs. 2, 8, and i, beneath the pivoted safety guard arm, is dispensed with, and a depending guard plate is employed instead, said depending plate being mounted upon or forming part of the pivoted guard arm member, and adapted to extend over the upwardly moving peripheral portion'of the saw, and into and over the slot in which the saw is mounted; and

F 6, is a view in transverse approximately vertical section, taken on irregular line 6 of Fig. 5, looking in the direction indicated by the arrows. plates or printing plates of varying thickinventioml provide a'bed or table 1 mount-ed upon a suitable sawing machine frame :2

rotatively rotative shaft l mounted in suitable bearlugs, and to which shaft the saw is fixed in any desired, ordinary or well known manner, all of which may be of any desired,

The bed shown slot' or groove 5 through which the saw projects upward through the bed and in T perpendicular relation to the top horizontal surface of the same,- in position to operate upon electrotype, stereo r pe orsimilar metallic plates or printing plates of varying thickness, to be sawed or trimmed. As sawing or trimming machines used for the purposes herein indicated are of various types which are 111- common use and well knownto those skilled in the art to which this invention relates it is deemed unnecessary and undesirable to describe thesame in detail herein, or to illustrate such a machine more fully than as herein described and shown. 7

An upright stationary guard 6, which may be in the form of a flat strip of metal, is mounted in the slot 5 in position to extend upward above the top surface of the bed adjacent to the upwardly-moving side of the saw, and is secured in position by means of bottom flange portions 7 and sefixed to the machine frame at apoint above' bearings in supporting brackets 11 and 12 which are secured to the bed or machine frame by means of screws 13, orsimilar securing means ,(see Figs. 1 and 2.) An operating lever leis fixed to the shaft 10 by means of a securingscrew 15, or other suitable securing means, so as to rock with the rock shaft, to raise and lower the guardsupporting arm 9. A boss 16 upon the machine frame is located in position to engage and limit the downward movement of the lever 1d; and a similar boss or stud 17 thelevel of the boss 16 is adapted to engage and support the lever 14: in its raised position, as shown in broken lines in Fig. 2.

, The upwardly and downwardly movable end of the arm 9 terminates in aslotted or hollow guard portion 18 which extends over the stationary guard. member 6 and is provided with side-frame or guard portions in the form of upper side bars 19 and lower side bars 20 located on opposite sides of the saw the forward extremities of said side bars being connected by means of a transverse upright end'piece 21 and inclosing side wall-portions 22 which may be made in one integral piece with the corresponding upper and lower side bars 19, 20. By providing side openings 23, 23 between the upper and lower side bars 19 and 20 on the opposite sides of-the saw, and an upper opening between the top side bars 19, and a slot 25 between side wall portions 26,26 of the guard member 18, the saw is permitted to rotate freely and without coming into actual contact with any of the parts of the guard, and the upper portion ofthe saw is shielded on opposite sides andcovered by the hollow guard, and is visible to the operator through said openings A set screw 27 in threaded engagement with the guard supporting arm 9 engages the top ofthe stationary guard member 6 already described, and is adapted to limit the downward movement of arm 9 and support said arm and the shield or guard upon said arm in operative position and at the desired height above the top surface of the bed.

A hollow adjustable shield or guard memher in the form of ahood-or hollow shield 28, is mounted upon and in, adjustable re1ation to the guard member 18 or slotted end portion of the arm 9, in position to inclose and cover said slotted guard member 18 and the inner frame-work comprising the upper side bars 19 and lower side bars 20 and connected parts already described.

The hollow outer shield or adjustable guard member 28 comprises in its construction a transverse top or end frame member 29 a transverse end-frame member 30, opposite side-frame members 31, 31, located on opposite sides of the saw and on the outside of the inner guard members already described, -S2L1Cl slde-frame members 31, 31 being-connected at their opposite extremities by means of said transverse frame members 29 and 30, so as to form a hollow frame which is open at the bottom and extends over and incloses the upper portion of the saw.

The outer adjustable shield or guard 28 is provided with a transparent top or cover plate 32 and transparent side plates 33, 33, all formed, by preference, of glass or similar suitable transparent material, and held in position by means of the transverse frame members 29 and 30 and side-frame members 31already described. A securing flange member or metallic strip 34 is removably secured in position upon the endframe member 30 andin position to overlap and removably hold in place the adjacent margin of the transparent top plate 32 (see Fig. 3.) A transverse anti-friction roller 35' is rotatively mounted in suitable bearings upon the forward or outer swinging end of the guard 28, being provided with a suitable axle 36 which is in parallel relation to the axis of the rock shaft 10 and the axis of the saw. This roller extends transversely with respect to the slot in which the saw is mounted and is adapted to prevent the bottoms of the. side-frame members 31 from coming into contact with the materialto be operated upon. 7

The top end-frame member 29 is provided with an elongated vertical slot 37 and with bearings 38, 38 on opposite sides of said slot; (see Figs. 1 and 3) and mounted in these hearings or supports 38, 38 is a transverse pin or stub shaft 39 on which is mounted an eccentric 10, the outer periphery of which is in engagement with the inner slotted guard member 18; and an operating handle or lever 41 is fixed to this eccentric or cam in any desired suitable or well known manner. Laterally projecting guiding pins or studs 42 are provided upon opposite sides of the guard member 18, to which they are secured in position to extend through corresponding inclined elongated transverse slots 43 in the adjacent side frame members 31 of the outer adjustable guard member or hood 28; and similar laterally projecting studs 44 are fixed to and in position to project laterally beyond the opposite sides of the inner side-frame members 22 and into inclined slots 45 in frame members 31.

With the parts constructed and arranged as above described, it is plain that when the lever 41 and adjusting eccentric or cam 40 are in the position shown in full lines in Fig. 3 the outer guard member or shield 28 will be supported in the position in which it is shown in full lines in said figure, that being the lowered operative position which it would occupy when in use in the operation of sawing or trimming plates which are comparatively thin or less than type-high. It is also plain that, by turning the lever 41 and eccentric 40 to the position in which they are shown in broken lines in said figure, the adjustable safety guard or shield member 38 will be supported in the position suitable for the accomplishment of the purposes for which it isintended, when in use in the operation of sawing or trimming metallic or other printing plates which are type-high as shown in broken lines in Fig. 3.

The adjustable shield or guard member 28 is thus adapted to be adjusted with facility to either lowered operative position or to upper operative position, with respect to the arm 9 and inner slotted guard member 18, according to the character of the work or thickness of the material to be operated upon.

When the arm.9, with the guard members supported thereon, is to be raised from the position in which it is shown in full lines in Fig. 2 to the position in which it is shown in broken lines in said figure, it is only neces- .sary to raise the operatinglever 14 located beneath the bed, from the position in which it is shown in full lines to the position in which it is shown in broken lines in said Fig. 2. Freedom of access to the saw is thus afforded, for any purpose, such, for instance, as cleaning or repairing the mechanism, or

* adjustment of parts.

By making the transparent walls of the outer hood or adjustable guard member of plate glass and making the framework or body of the hood of metal, the part of the saw over which the hood or guard extends is exposed and at all times visible to the operator, and the eyes of the operator are protected from fiying chips or cuttings while the fingers of the operator are thoroughly protected from being injured by the saw. The

stationary guard member adjacent to'the upwardly moving peripheral portion of the saw and the slotted guard member which extends over the stationary guard member and on opposite sides of the upwardly moving peripheral portion of the saw which passes through the slot, serve to prevent chips and cuttings from flying in such a manner as to break or injure any of the glass or other parts of the safety guard; and the outer hollow shield or guard member being adjustable, the device possesses the advantages of safety combined with convenience of adjustment without in any way interfering with or detracting from the efiiciency or speed of operation.

In the form of the device embodying my invention as shown in Figs. 5 and 6, the pivoted arm 9 has a slotted end portion 46 which extends over the upwardly moving peripheral portion of the saw and has depending side fiange portions 47 which form the opposite side wallsof a slot 48 and extend on opposite sides of the saw which extends into said slot (see Figs. 5 and 6); and a depending guard-plate member 49 is fixed to the slotted end portion 46 of the arm 9, in position to extend over the slot 5 in the bed 1 in which the saw is mounted, and over the upwardly moving peripheral portion of the saw, said guard plate being in alinement with the slot 48 and in the same vertical plane with the body of the 46 in position to extend over the'saw. And a downwardly projecting shoulder portion 51 extends downward beyond the supporting bottom edge portion and into the slot 5 in the bed or table 1, when the pivoted arm member 9 with its slotted end portion 46 and depending guard plate member 49' are in lowered position. In all other respects, the pivoted guard arm member 9 with its slotted end portion 46 is constructed and arranged and adapted to operate in substantially the same manner already described in connection with Figs. 1, 2, 3 and a of the drawings. And. a hollow outer hood-shaped guard member 28 made in two separate parts or halves rigidly secured together by means of transverse screws or rivets 52, as shown in Figs. 5 and 6, is mounted upon and in adjustable relation to the guard arm member 9 and its slotted end portion 46, as shown in said Figs. 5 and 6, said outer hood-shaped member having transparent wall portions 33, and adjusting eccentric and lever mechanism all constructed and adapted to operate in substantially the same manner in all respects, as already described in connection with Figs. 1, 2, 3,

and 4:, and as shown in said figures. The adjustable hood member 28 is provided with bottom cushioning strips 52 of compressible material or fabric, such, for instance, as paper, for preventing the metallic parts from coming into contact with the plates to be operated upon. 7

I claim 1 r 1. In a safety shield for saws, the combination of a guard arm member, means for pivotally supporting said guard arm member in position to swing in the same vertical plane with and extend over the upwardly moving peripheral portion of a saw, a vertical guard plate mounted in position to extend over and in the same vertical plane with such saw and below the free end of said pivoted guardarm, an outer hood-shaped member adjustably mounted upon said guard arm member and having transparent wall portions adapted to extend over and in position to inclose the upper peripheral portion of the saw, said hood being adapted to be raised and lowered bodily with respect a to said pivoted guard arm to different adjusted. positionsover the saw, and having its bottom margin in a horizontal plane in each of such adjusted positions, and mechanical means for raising and lowering said adjustable hood to different adjusted positions with respect to the pivotedguard arm. r

2. In a safety shield for saws, the combination of a guard-arm member having a vertically slotted free end portion adapted to extend over and on opposite sides oI the upwardly moving peripheral portion of a circular saw, said guard armbeing adapted to swing in the same vertical plane in which the saw is located, means for pivotally supporting said guard arm, a vertical guard 2 plate located in the same vertical plane with .saw, and'means for raising and lowering the adjustable hood with respect to the slotted end oftheguard arm.

3. In a safety shield for saws, the combination of a guard arm member, means for pivotally supporting said guard arm memberin operative position adjacent to the upwardly moving peripheral portion of a saw, a'hollow guard member arranged inposition to engage said pivoted guardarm member and extend over the ,upper peripheral portion of such saw, said hollow guard memher having elongated inclined slots inthe side walls thereof, laterally projecting pins on thepivoted guard arm member and in sliding engagement with said slots, rotative' adjusting mechanism mounted in eccentric relation to a suitable pivot and in operative engagement with said pivoted guard arm member and said hollow guard member, for raising and lowering the hollow guard member to different adjusted positions with 'respect to the pivoted guard arm member, and

means for operating the pivoted guard arm member.

Si ned atChicago, Illinois, July 18, 1918.

I, CHRISTIAN N. SMITH Nitnesses: I

DAVID H. FLETCHER, W. HARDING. 

